The dark mysticism of the ancient East and the agnosticism of modern times here join hands. This modern method of separating knowledge and faith is, as we all know, a prominent feature of modern thought. Knowledge, that is, cognition by reason, is said to exist only in the domain of the natural sciences and history. Of what may be beyond these we can have no true knowledge. Here, too, _Kant_ has led the way; for the important result of his criticism is his incessant injunction: we can have true knowledge only of empiric objects, never of things lying beyond the experience of the senses; our ideas are merely subjective constructions of the reason which obtain weight and meaning only by applying them to objects of sense experiment. Hence God, immortality, freedom, and the like, remain forever outside the field of our theoretical or cognitive reason. Nevertheless _Kant_ did not like to drop these truths. Hence he constructed for himself a conviction of another kind. The “practical reason” is to guide man’s action in accomplishing the task in which her more timid sister, theoretical reason, failed. And it does it, too. It simply “postulates” these truths; they are its “_postulates_,” since without them moral life and moral order, which it is bound to recognize, would be impossible. No one knows, of course, whether this be truth, but it ought to be truth. _Stat pro ratione voluntas._ The Gordian knot is cut. “It is so,” the will now cries from the depths of the soul, “I believe it”; while the intellect stands hesitatingly by protesting “I don’t know whether it is so or not.” Doubt and conviction embrace each other; Yes and No meet peacefully. “I had to suspend knowledge,” _Kant_ suggests, “in order to make room for faith” (Kritik der reinen Vernunft, 2. Vorrede). “It is an exigency of pure practical reason based on duty,” he further comments on his postulate, “to make something the highest good, the object of my will, in order to further it with all my power. Herein, however, I have to assume its possibility, and therefore its conditions, viz., God, freedom, and immortality, because I cannot prove them by speculative reason, nor yet disprove them.” Thus “the just man may say I wish that there be a God; I insist upon it, I will not have my faith taken from me” (Kritik der prakt. Vernunft, 1. Teil, 2. Buch, 2 VIII). Others have followed the lead of _Kant_. For philosophers, Protestant theologians, and modernists, he has become the pilot in whom they trust.